target/riscv: fix instructions count handling in icount mode

target/riscv: fix instructions count handling in icount mode

When icount is enabled, rather than returning the virtual CPU time, we
should return the instruction count itself. Add an instructions bool
parameter to get_ticks() to correctly return icount_get_raw() when
icount_enabled() == 1 and instruction count is queried. This will modify
the existing behavior which was returning an instructions count close to
the number of cycles (CPI ~= 1).

Signed-off-by: Clément Léger <cleger@rivosinc.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Message-ID: <20240618112649.76683-1-cleger@rivosinc.com>
Signed-off-by: Alistair Francis <alistair.francis@wdc.com>